Summary:
If your web application'''s success depends on how quickly and easily users can make transactions, PayPal APIs provide effective solutions you can'''t afford to overlook. This concise book takes you hands-on through several options to help you determine the best choice for your situation, whether you'''re collecting money via websites or mobile apps for products and services, donations, or anything else.

In each chapter, you'''ll work with a different PayPal API by integrating it into the book'''s sample application, using Python and the Google App Engine framework. This expanded edition introduces two new options: Express Checkout for Digital Goods and Instant Payment Notifications, complete with sample project code. By the end of this book, you'''ll understand how to take full advantage of PayPal and its powerful features.

Learn PayPal API basics, and get an introduction to Google App Engine

Explore the Express Checkout option, and understand what distinguishes it from other generic workflows

Embed the payment process into your site with no mention of PayPal, using Website Payments Pro

Use the Instant Payment Notifications you receive as triggers to take follow-up action

GDNet Staff Review:PayPal APIs Up and Running is about the dozenth book about how to talk to PayPal from within your application. And this isn't necessarily a market-clogging problem, mainly because PayPal has been around for quite some time, and there are literally about a dozen different ways to talk to PayPal depending on how you are selling your product/add-on/microtransaction within or outside of your game. If you want to sell games from your website or sell virtual gizmos from inside your game, you can do it from PayPal. But the way you will talk to the system will likely be quite different.

The book isn't especially long. It is about 120 pages, which seems to be the norm for the latest crop of more narrowly-focused technical books. And, as you'd expect, you cannot comprehensively cover all of PayPal's API's in that short a space, so PayPal APIs Up and Running concentrates on PayPal's NVP (name-value-pair) system, which is a two-way communication that's suitable for embedding entirely within a game.

One complaint I have about the book is its use of Google App Engine and Python for all of the server-side code. While GAE is certainly a robust and proven system, it is not the most popular thing out there. If your server code is not GAE and you plan to talk to your app via Perl or PHP, the book suggests you check the PayPal online docs.

Mind you, this is not a complete deal-breaker. It is still a very good "one sitting" overview about how to talk to PayPal. And the price ($15 on Kindle at the time of this review) is a fair price for such an overview if you find yourself needing to learn about PayPal, the API's, and the PayPal developer tools (like the Sandbox) in a hurry. I just fear the book might be a little too narrow for someone who wants to get "up and running". Especially when you are competing with PayPal's very extensive online developer documentation.